DALLAS (CBSDFW.COM) – As drivers create a run at gas stations across North Texas, some people wonder about the higher than normal prices at the pumps.

Price gouging is illegal. That’s the first sentence on the Texas Attorney General’s web page on the topic. And the state has the authority to prosecute any business engaging in price gouging after a disaster is declared by the governor.

But what’s the difference between supply-and-demand pricing, and price gouging? State law says it’s selling or leasing fuel, food, medicine or another necessity at an exorbitant or excessive price.

When storms like Hurricane Harvey damage Texas oil refineries prices will jump.

The State Attorney General says the price can include cost of refining and distribution, taxes, and the retail station’s operating cost. And with all those variables, it’s tough to determine what exactly is a fair price… and what is price gouging.

If you suspect price gouging is happening, please click here to file a complaint with the Texas Attorney General’s office.